Refrigerator

ABSTRACT

There is provided a refrigerator. The refrigerator includes a compressor for compressing a refrigerant, a condenser for heat-exchanging the compressed refrigerant with ambient air, an expansion member for expanding the heat-exchanged refrigerant, a condensing pipe interconnecting the condenser and the expansion member, a vaporizer for heat-exchanging the expanded refrigerant with a cooling air in a freezing or cooling chamber, and a suction pipe interconnecting the vaporizer and the compressor and associated with the condensing pipe to allow a heat exchange between the suction pipe and the condensing pipe.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a refrigerator, and more particularly,to a refrigerator having an improved cooling cycle that can reduce thepower consumption and improve a coefficient of performance (COP) byefficiently using thermal energy wasted during a refrigerant isintroduced into an expansion valve through a condenser.

2. Description of the Related Art

A refrigerator is an electrical appliance for cooling or freezing foodto preserve the food.

Generally, the refrigerator can be classified into a top mountrefrigerator in which a freezing chamber and a chilling chamber arepartitioned up and down, a bottom freezer refrigerator in which afreezing chamber and a cooling chamber are partitioned down and up, aside-by-side refrigerator in which a freezing chamber and a coolingchamber are partitioned left and right.

Especially, the side-by-side refrigerator has a freezing and coolingchamber doors that are opened toward both sides. The side-by-side has arelatively volume compared with other types and a variety of functions.Therefore, the side-by-side refrigerators have been widely used inrecent years.

Many of the prior art refrigerators are an exposure type where acondenser is exposed to an external side. That is, A refrigerant flowingalong a pipe connecting the condenser to a capillary maintains atemperature of about 40-45° C. while a refrigerant flowing along asuction pipe connecting a vaporizer to a compressor maintains atemperature of about −25-−30° C. In addition, in the prior artrefrigerator, in order to improve the COP, a portion of the suction pipeis designed to contact the capillary. That is, when the heat istransferred from the capillary to the suction pipe, a temperature of thesuction pipe increases to pre-heat the refrigerant directing toward thecompressor, thereby reducing the compressing work. The reduction of thecompressing work increases the COP and reduces the electric powerconsumption.

However, in the cooling cycle, the heat generated from the refrigerantflowing from the condenser toward the capillary is wasted to the ambientair. That is, the heat discharged during the refrigerant passed throughthe condenser flows toward the capillary cannot be efficiently used,thereby generating a cyclic minor loss.

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to a refrigerator thatsubstantially obviates one or more problems due to limitations anddisadvantages of the related art.

An object of the present invention is to provide a refrigerator havingan improved cooling cycle that can reduce the power consumption andimprove a coefficient of performance (COP) by efficiently using thermalenergy wasted during a refrigerant is introduced into an expansion valvethrough a condenser.

Additional advantages, objects, and features of the invention will beset forth in part in the description which follows and in part willbecome apparent to those having ordinary skill in the art uponexamination of the following or may be learned from practice of theinvention. The objectives and other advantages of the invention may berealized and attained by the structure particularly pointed out in thewritten description and claims hereof as well as the appended drawings.

To achieve these objects and other advantages and in accordance with thepurpose of the invention, as embodied and broadly described herein,there is provided a refrigerator including: a compressor for compressinga refrigerant; a condenser for heat-exchanging the compressedrefrigerant with ambient air; an expansion member for expanding theheat-exchanged refrigerant; a condensing pipe interconnecting thecondenser and the expansion member; a vaporizer for heat-exchanging theexpanded refrigerant with a cool air in a freezing or cooling chamber;and a suction pipe interconnecting the vaporizer and the compressor andassociated with the condensing pipe to allow a heat exchange between thesuction pipe and the condensing pipe.

In another aspect of the present invention, there is provided arefrigerator including: a compressor for compressing a refrigerant; acondenser for condensing the compressed refrigerant with ambient air; anexpanding valve for expanding the condensed refrigerant; and a vaporizerfor heat-exchanging the expanded refrigerant with cool air of a freezingor cooling chamber, wherein a portion of a suction pipe corrected to aninlet of the compressor contacts a portion of a condensing pipeconnected to an outlet of the condenser to allow for a heat exchangebetween the suction pipe and the condensing pipe.

In still another aspect of the present invention, there is provided arefrigerator comprising: a suction pipe interconnecting a vaporizer anda compressor; an expansion member heat-exchanging with a refrigerantflowing along the suction pipe; and a condensing pipe heat-exchangingwith the refrigerant flowing along the suction pipe at an inlet of theexpansion member.

In still yet another aspect of the present invention, there is provideda refrigerator comprising: pipes connected to each other such that arefrigerant flowing toward an inlet of a compressor after passingthrough a vaporizer can be heat-exchanged but not mixed with arefrigerant passing through an expansion member and/or a refrigerantpassed through a condenser.

According to the present invention, the waste heat discharged from therefrigerant passed through the condenser is efficiently used during thecompression process, thereby reducing the compressing work andincreasing the COP.

Furthermore, since the compressing work is reduced, the electric powerconsumption for driving the compressor can be reduced.

In addition, since the pipe interconnecting the condenser and thecapillary and the suction pipe is bonded in a helix shape, the heatexchange area increases to improve the space efficiency of the machineroom, thereby reducing the overall volume of the refrigerator.

It is to be understood that both the foregoing general description andthe following detailed description of the present invention areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiment (s) of the invention andtogether with the description serve to explain the principle of theinvention. In the drawings:

FIG. 1 is a schematic view of a cooling system of a refrigeratoraccording to an embodiment of the present invention;

FIG. 2 is a perspective view of a second heat-exchanging portion formedon a portion of a suction pipe contacting a condensing pipe in a coolingcycle according to an embodiment of the present invention; and

FIG. 3 is a P-H diagram illustrating a phase variation of a refrigerantduring the cooling system of the present invention is operated.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. The invention may, however, be embodied in many differentforms and should not be construed as being limited to the embodimentsset forth herein; rather, these embodiments are provided so that thisdisclosure will be thorough and complete, and will fully convey theconcept of the invention to those skilled in the art.

FIG. 1 is a schematic view of a cooling system of a refrigeratoraccording to an embodiment of the present invention.

Referring to FIG. 1, a refrigerator 10 having a cooling system accordingto an embodiment of the present invention includes a condensing pipealong which a refrigerant passed through a condenser flows and a suctionpipe along which a refrigerant introduced into the compressor flows. Thecondensing pipe and a suction pipe contact each other to perform theheat exchange.

The refrigerator 10 includes a compressor 11 for compressing therefrigerant, a condenser 12 into which the refrigerant compressed with ahigh temperature and a high pressure by the compressor 11 is introduced,a capillary 14 for cooling the high temperature and high pressurerefrigerant passed through the condenser 12 to a low temperature and alow pressure, a vaporizer 15 into which the refrigerant, which isconverted into a two-phase state (a liquid phase and a vapor phase)while passing through the capillary 14, is introduced to heat-exchangewith cool air of the freezing and cooling chambers, and a phaseseparator 16 for separating the refrigerant passed through the vaporizer15 into vapor and liquid.

In addition, the refrigerator 10 further includes a dryer 13 interposedbetween the condenser 12 and the capillary 14, a condensing pipe 17interconnecting the condenser 11 to the dryer 13, and a suction pipe 18connecting the phase separator 16 to the compressor 11. In addition, thesuction pipe 18 has a first heat-exchanging portion 191 contacting thecapillary 14 for the heat-exchange and a second heat-exchanging portion192 contacting the condensing pipe 17 for the heat-exchange.

With the above-described refrigerator, the suction pipe 18 receives heatfrom the capillary 14 and the condenser pipe 17 to increase thetemperature of the refrigerant flowing toward the compressor 11. As thetemperature of the refrigerant flowing toward the compressor 11increases, the compressing work of the compressor is reduced. At thispoint, as the heat is transferred from the capillary 14 to the suctionpipe 18, the temperature of the refrigerant is reduced at the inlet ofthe vaporizer 15. Therefore, an amount of the heat-exchange between thecool air in the refrigerator and the refrigerant in the vaporizer 15increases. As a result, the time for reducing the cool air to a targettemperature is reduced. In addition, the refrigerant flowing along thecondensing pipe 17 releases its heat to the suction pipe 18, therebyincreasing an amount of the refrigerant that is liquefied. Therefore,the change of success for introducing air into the capillary 14 isreduced as compared to the prior art refrigerator.

The refrigerant phase that varies by the above-described cooling cycleand the COP in the refrigerator of the present invention will now bedescribed in more detail.

FIG. 2 is a perspective view of a second heat-exchanging portion formedon a portion of the suction pipe contacting the condensing pipe in thecooling cycle according to an embodiment of the present invention.

Referring to FIG. 2, the second heat exchange portion 192 is formed by ahelix or spiral contact between the condensing pipe 17 and the suctionpipe 18.

That is, since the condensing pipe 17 and the suction pipe 18 contacteach other, the waste heat discharged from the condensing pipe 17 istransferred to the suction pipe 18. Here, likewise the contact betweenthe capillary 14 and the suction pipe 18, the condensing pipe 17 maylinearly contact the suction pipe. However, in order to reduce theelectric power consumption, it is preferable that each length of thecondensing and suction pipes 17 and 18 is about 80-100 cm. Therefore,when the condensing pipe 17 contacts the suction pipe linearly, it isdifficult to take a space for the pipes 17 and 18 in a machine room. Tosolve this problem, the pipes 17 and 18 are coiled in the helix orspiral shape. In this case, the length of the pipes 17 and 18 is reducedto 10-12 cm that is almost identical to that of the dryer 13. Therefore,the space for receiving the second heat-exchanging portion 192 in themachine room can be sufficiently obtained. Here, the contacting portionbetween the condensing pipe 17 and the suction pipe 18 may be spirallycoiled or bent or curved at a plurality of locations.

Instead of making the condensing and suction pipes 17 and 18 contacteach other, the condensing pipe 17 may extends through the inside of thesuction pipe 18. In this case, it is preferable that the refrigerant ofthe suction pipe 18 flows in a direction opposite to that where therefrigerant of the condensing pipe 17 flows to enhance the heat exchangeefficiency.

That is, as the condensing pipe 17 extends through the inside of thesuction pipe 18, the waste heat discharged through the condensing pipe17 is fully transferred to the refrigerant flowing along the suctionpipe 18, thereby increasing the thermal transfer rate up to 100% andthus dramatically reducing the electric power consumption as compared tothe case where the suction and condensing pipe contact each other attheir outer surfaces.

In addition, when the condensing and suction pipes 17 and 18 are coiledin the helix shape, the contacting area between the condensing andsuction pipes 17 and 18 can increase to the maximum level in the limitedmachine room by properly adjusting a diameter of the helix.

FIG. 3 is a P-H diagram illustrating a phase variation of therefrigerant during the cooling system of the present invention isoperated.

Referring to FIG. 3, in an ideal cooling cycle, the refrigerant goingthrough compressing, condensing, expanding, and vaporizing processesgoes through a-b-c-d.

Describing a refrigerant circulation in the cooling cycle, therefrigerant is compressed to a high temperature and high pressure by thecompressor 11. The compressed refrigerant flows into the condenser 12 tobe phase-changed into liquid by heat exchange with ambient air. Theliquid refrigerant passed through the condenser 12 is directed to thecapillary 14 via the dryer 13. Here, moisture contained in therefrigerant flowing into the capillary 14 is eliminated by the dryer.

Meanwhile, the refrigerant introduced into the capillary 14 isphase-changed into two-phase state (i.e., vapor and liquid states) witha low temperature and low pressure through a throttling process. Then,the two-phase refrigerant is introduced into the vaporizer 15 andheat-exchanged with the cool air of the freezing or cooling chambers. Apart of the refrigerant is phase-changed from a liquid-phase into avapor-phase by the heat transferred from the cool air in the freezing orcooling chambers. Then, the refrigerant passed through the vaporizer 15passes through the phase-separator, in the course of which the liquid isfiltered. Therefore, only the liquid refrigerant is reintroduced intothe compressor 11.

A heat exchange between the refrigerants is realized by the heatconduction at the first heat-exchanging portion 191 where the suctionpipe 18 contacts the capillary 14. In addition, an additional heatexchange between the refrigerants is realized by the heat conduction atthe second heat-exchanging portion 192 where the suction pipe 18contacts the condensing pipe 17.

That is, in the ideal cooling cycle,

Compressing Work [(w_(c))_(ideal)]=h_(b)−h_(a),

Condensing Heat [(q_(out))_(ideal)]=h_(b)−h_(c),

Expanding Heat=0, and

Vaporizing Heat [(q_(in))_(ideal)]=h_(a)−h_(d).

In addition, in a real cooling cycle that is actually applied to arefrigerator, since the heat is transferred from the capillary 14 to thesuction pipe 18 by allowing the capillary 14 to contact the suction pipe18, the refrigerant goes through e-b-c-g.

That is, in the real cooling cycle,

Compressing Work [(w_(c))_(real)]=h_(b)−h_(e),

Condensing Heat [(q_(out))_(real)]=h_(b)−h_(c),

Expanding Heat=h_(c)−h_(g), and

Vaporizing Heat [(q_(in))_(real)]=h_(a)−h_(g)

Meanwhile, in the cooling cycle according to the present invention,since there is a heat exchange between the condensing pipe 17 and thesuction pipe 18 that contact each other, the temperature of therefrigerant flowing toward the compressor 11 further increases while thetemperature of the refrigerant flowing toward the vaporizer furtherdecreases. Therefore, in the cooling cycle according to the presentinvention,

Compressing Work [(w_(c))_(present)]=h_(b)−h_(f),

Condensing Heat [(q_(out))_(present)]=h_(b)−h_(c),

Expanding Heat=h_(s)−h_(k), and

Vaporizing Heat [(q_(in))_(present)]=h_(a)−h_(k).

That is, since there are heat exchanges between the capillary 14 and thesuction pipe 18 and between the condensing pipe 17 and the suction pipe18, the sum of the discharged expanding heat (h_(s)−h_(k)) and thecondensing heat (hc0hs) is to be identical to a heat value absorbed bythe suction pipe 18. Therefore, the compression work is reduced ascompared to that of the prior art cooling cycle.

Furthermore, the compression work can be dramatically reduced dependingon a contacting length of the condensing pipe 17 and the suction pipe 18as compared to the prior art cooling cycle.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present invention. Thus,it is intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

1. A refrigerator comprising: a compressor for compressing arefrigerant; a condenser for heat-exchanging the compressed refrigerantwith ambient air; an expansion member for expanding the heat-exchangedrefrigerant; a condensing pipe interconnecting the condenser and theexpansion member; a vaporizer for heat-exchanging the expandedrefrigerant with a cool air in a freezing or cooling chamber; and asuction pipe interconnecting the vaporizer and the compressor andassociated with the condensing pipe to allow a heat exchange between thesuction pipe and the condensing pipe.
 2. The refrigerator according toclaim 1, wherein an outer circumference of the condensing pipe contactsan outer circumference of the suction pipe by a predetermined length. 3.The refrigerator according to claim 1, wherein the condensing pipe andthe suction pipe are coiled in a helix shape.
 4. The refrigeratoraccording to claim 1, wherein the condensing pipe extends through aninside of the suction pipe.
 5. The refrigerator according to claim 1,wherein a part of the suction pipe contacts the expansion member.
 6. Therefrigerator according to claim 1, wherein the refrigerant flows alongthe suction pipe in a direction opposite to that where the refrigerantflows along the condensing pipe.
 7. A refrigerator comprising: acompressor for compressing a refrigerant; a condenser for condensing thecompressed refrigerant with ambient air; an expanding valve forexpanding the condensed refrigerant; and a vaporizer for heat-exchangingthe expanded refrigerant with cool air of a freezing or cooling chamber,wherein a portion of a suction pipe connected to an inlet of thecompressor contacts a portion of a condensing pipe connected to anoutlet of the condenser to allow for a heat exchange between the suctionpipe and the condensing pipe.
 8. The refrigerator according to claim 7,wherein the portion where the suction pipe contacts the condensing pipeis coiled with a predetermined curvature.
 9. The refrigerator accordingto claim 7, wherein the contact portion between the suction pipe and thecondensing pipe is bent or curved at a plurality of locations toincrease a heat-exchange area between the suction pipe and thecondensing pipe.
 10. The refrigerator according to claim 7, wherein thesuction pipe contacts the condensing pipe in a way that the refrigerantsin the pipes mutually flow in an opposite direction.
 11. Therefrigerator according to claim 7, wherein the suction pipe contacts apart of an outer circumference of the expansion valve to allow for theheat exchange between refrigerants flowing the suction pipe and theexpansion valve.
 12. The refrigerator according to claim 7, wherein thesuction pipe contacts the expansion valve to realize a primary heatexchange between the refrigerants flowing along the suction pipe and theexpansion valve and the suction pipe further contacts the condensingpipe to realize the secondary heat exchange between the refrigerantsflowing along the suction pipe and the condensing pipe.
 13. Arefrigerator comprising a suction pipe interconnecting a vaporizer and acompressor; an expansion member heat-exchanging with a refrigerantflowing along the suction pipe; and a condensing pipe heat-exchangingwith the refrigerant flowing along the suction pipe at an inlet of theexpansion member.
 14. The refrigerator according to claim 13, whereinthe refrigerant flowing along the suction pipe after passing through thevaporizer primarily absorbs heat from the expansion member andsecondarily absorbs heat from the refrigerant flowing along thecondensing pipe.
 15. The refrigerator according to claim 13, wherein therefrigerant flowing along the suction pipe is heat-exchanged but notmixed with a refrigerant flowing along the expansion member or thecondensing pipe.
 16. The refrigerator according to claim 13, where apart of an outer circumference of the expansion member contacts a partof an outer circumference of the suction pipe for a heat exchangetherebetween.
 17. The refrigerator according to claim 13, wherein thesuction pipe and the condensing pipe partly contact each other at theirouter circumferences or the suction pipe extends through the inside ofthe condensing pipe.
 18. The refrigerator according to claim 13, whereina part of the suction pipe contacts the expansion member or thecondensing pipe and is coiled together at a predetermined curvature. 19.A refrigerator comprising: pipes connected to each other such that arefrigerant flowing toward an inlet of a compressor after passingthrough a vaporizer can be heat-exchanged but not mixed with arefrigerant passing through an expansion member and/or a refrigerantpassed through a condenser.